Baking Slapjacks, Yellowstone National Park, 1870s

This photo was made by William Henry Jackson when he accompanied geological survey conducted by Ferdinand Hayden. Hayden organized a geologic survey of the Yellowstone area, which was an unknown land in that times. Hayden asked Jackson to come with the expedition and later his photographs of Yellowstone helped in convincing Congress to name the park as the first national park. It happened on March 1, 1872